18.9.97.1.1 Ensure 'Allow Basic authentication' is set to 'Disabled' - Client

Information

This policy setting allows you to manage whether the Windows Remote Management (WinRM) client uses Basic authentication.

The recommended state for this setting is: Disabled.

Note: Clients that use Microsoft's Exchange Online service (Office 365) will require an exception to this recommendation, to instead have this setting set to Enabled. Exchange Online uses Basic authentication over HTTPS, and so the Exchange Online authentication traffic will still be safely encrypted.

Rationale:

Basic authentication is less robust than other authentication methods available in WinRM because credentials including passwords are transmitted in plain text. An attacker who is able to capture packets on the network where WinRM is running may be able to determine the credentials used for accessing remote hosts via WinRM.

Solution

To establish the recommended configuration via GP, set the following UI path to Disabled:

Computer Configuration\Policies\Administrative Templates\Windows Components\Windows Remote Management (WinRM)\WinRM Client\Allow Basic authentication

Note: This Group Policy path is provided by the Group Policy template WindowsRemoteManagement.admx/adml that is included with all versions of the Microsoft Windows Administrative Templates.

Impact:

None - this is the default behavior.

Default Value:

Disabled. (The WinRM client does not use Basic authentication.)

See Also

https://workbench.cisecurity.org/files/2700